Improvement in steam-engines



No. 122,049. v Patented Dec-19,1871. 5 711/0367 is [Zea/2a 17239 5726 UNITED STATES PATENT QFFIGE.

ASSIGNMENTS, TO JAMES R. TEAL, OF SAME PLACE.

lMPROVEMENT lN STEAM-ENGINES.

Specification forming part of Letters Patent No. 122,049, dated December 19, 1871.

To all whom it may concern:

Be it known that I, FRANCIS MOTLEY, of Phoenixville, in the county of Chester and State of Pennsylvania, have invented a new and Improved Steam-Engine; and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing forming part of this specification, in which- Figure 1 represents a horizontal section of the steam-chest, showing the several slide-valves therein in detailed vertical sections so as to make their respective positions and functions better understood. Fig. 2 is a detail vertical section of the same taken on the plane of the line as as, Fig. 1. Fig. 3 is avertical section of the same taken on the plane of the line y y, Fig. 1. Fig. 4 is an inverted plan view of the slide-valves.

Similarletters of reference indicate corresponding parts.

The object of this invention is to provide a means for moving the slide-valve in a steanrchest by direct action of the live steam and without the use of a link-motion or other mechanism conn ecting with the machinery. The invention consists in the application to the steam-chest of a secondary slide-valve, which, when acted upon by the steam reaching it through certain channels, will open certain steam-passages to the main slidevalve and adjust the latter to the necessary ch an ge of stroke. Thus the requisite motion is obtained by the direct action of live steam. and all danger of dead-lock to the slide-valve obviated by the application of the secondary valve, which, by regulating the action of steam on the main slide makes the motion of the same positive. The invention also consists in the application of pistons and cylinders to both the said valves to obtain the requisite steam-power for moving the same; and, finally, in the arrangement of the several channels for conducting steam from under and to the several valves and ports, as hereinafter m ore fully described.

A in the drawing represents a steam-cylinder of suitable construction, containing a piston, B, and supporting a steam-chest, 0. Within the steam-chest is arranged the slide-valve D, which moves over the ordinaryinlet-ports a. b and over the exhaustport c in the well-known manner, regulating thereby the motion of the piston in the cylinder and the admission of steam to the latter. A rod, d, connects the slide-valve D with a small piston, E, which works within a small cylinder, F, as shown, the said cylinder being afiixed to one end of the steam-chest, or otherwise applied. The cavity in the under side of the slide-valve for connecting the inlet-ports respectively, with the exhaust does not extend over the entire base of the slide, but leaves a broad enough margin on the same for three more cavities, f, g, and h, which are in line, as shown in Fig. 4. That portion of the slide valve which contains the said cavities f, g, and h moves over four ports, 6, k, and Z, in the steam-chest. The two inner ports, j and k, are, by channels on a, respectively connected with the cylinder A near the ends of the same. The outer ports, iand l, are, by channels 0 and p, respectively connected with the inner andouter ends of a small cylinder, G, which is affixed to the steam-chest, as shown. The courses of the channels 0 p are indicated by dotted lines in Fig. 1. The cavities f and h in the valve D are, by grooves 1', connected with the main exhaust-cavity c of the same, as in Fig. 4. The cylinder G contains a piston, H, which is, by a rod, t, connected with a secondary slide-valve, I, within the steam'chest. This secondary valve moves over three ports, u, v, and w, of which the outer, a and w, are, by channels .90 and 3 respectively connected with the ends of the cylinder F, while the central one, r, leads to the exhaust-pipe. The cavity 2 of the valve I connects the exh aust-port o with one of the others, leaving the third port open to the live steam.

The operation is as follows When the piston B moves toward the end of the cylinder A, near whichit is shown in Fig. 3, it will, near the end of its stroke, open the end of the channel m to the steam. This will lead steam, via the said channel m, cavity g, and channel 0, to the inner end of the cylinder G, causing the piston H to move outwardly and pull the valve I along so as to expose the port 10 to the live steam in the steam-chest. The steam will then enter through the channel y, the outer end of the cylinder F, and push the piston E inwardly, thereby moving the slide-valve D so as to expose the port a to live steam and reverse the movement of piston B. The slide-valve is then also brought in position to receive steam through the channel a at the end of the next stroke, and convey it, by the cavity g, to the channel 10 and outer end of G, whereby the valve I will again be shifted to reverse once more the motion of the main piston. The cylinder F exhausts into the cavity 2 and port 1;; the cylinder G into one of the ports 1' or Z, cavities f or h, and thence, through the grooves 1", into 0. The mechanism acts thus entirely automatic Without danger of interruption.

The secondary valve is important in its application, as it forms a barrier between the action of the piston B and that of E, making the latter independent of the former and obviating thereby the danger of having the whole adjustment stopped on the dead-center.

Having thus described my invention, I claim as new, and desire to secure by Letters Patent-- l. The secondary slide-valve I, arranged with- Witnesses GEO. W. MABEE, ALEX. F. ROBERTS. (V150) 

